Each of the pictures in the grid represents a word (or abbreviation) as shown in the grid below:

The plus and minus signs along with pictures should evoke the idea of a rebus, and in fact a continuous path can be drawn, starting and ending with the in and out arrows and using each picture once, to form a series of rebuses, each starting with a picture with no plus/minus sign. These rebuses resolve to the names of human bones (clued by the “remains” in the flavortext, as well as the title, which is a catchphrase of the Star Trek character nicknamed Bones) but with one letter missing from each bone. (Note that the subtracted words are always unbroken substrings, rather than random arrangements of letters.)

1. STEP + DRUM - PD = STERUM (STER[N]UM)
2. IBAR + C + HULA - ARCH = IBULA ([F]IBULA)
3. CLAP + ATV - PAT + ICE = CLAVICE (CLAVIC[L]E)
4. HUMP + HORUS - PHO = HUMRUS (HUM[E]RUS)
5. MESA + FETA - SAFE + CAGE + NEPAL - GENE (METACA[R]PAL)
6. DISCOVER - DISCO + WALT + ZEBRA - WALTZ = VEREBRA (VER[T]EBRA)
7. SCAR + UMP - RUM + LA = SCAPLA (SCAP[U]LA)
8. MAN + DIO + TABLE - IOTA = MANDBLE (MAND[I]BLE)
9. PAW + RENE - WREN + LLAMA - MA = PAELLA (PA[T]ELLA)
10. MALI + PLUS - IP = MALLUS (MALL[E]US)
11. PESO + DAVIS - SODA = PEVIS (PE[L]VIS)
12. TRAP + ZITI + GUM - TIG = TRAPZIUM (TRAP[E]ZIUM)

The missing letters spell the phrase NFLER TUITELE. Former NFL player Maugaula Tuitele is better known by the nickname ULA. This is also one letter short of a bone name: ULNA, the final answer to this puzzle.